Fire collar

ABSTRACT

A fire collar or fire damper for location within a concrete slab of a building. The device incorporates a damper arrangement ( 12 ) and a heat detector ( 18, 19 ) comprising a metal alloy or lead which melts when a present temperature is reached, causing the damper arrangement to seal off associated pipework or ducting.

FIELD OF THE INVENTION

This invention relates to a device for preventing fire from spreadingfrom one side of a partition to another by way of pipework or ducting inthe partition. In particular, the invention is primarily concerned witha new form of fire damper and a fire collar for location in a concreteslab separating the floors and walls of multi-floor buildings.

BACKGROUND OF THE INVENTION

A common type of fire collar comprises a metal collar which is fastenedaround a concrete slab-penetrating plastics material pipe in the regionwhere it traverses the slab; the collar enclosing an intumescentmaterial. When a fire on one side of the concrete slab reaches asufficient intensity to melt the pipe where it penetrates the slab, italso causes the intumescent material to expand and seal off the voidleft by the melted pipe. In this way, a barrier is formed to prevent thespread of the fire to the other side of the concrete slab.

A major problem with this type of fire collar is that the time taken forthe intumescent material to form a seal can be too long in rapidlyadvancing fires with the result that the fire can still spread to theother side of the partition.

A recent attempt to overcome this problem is a fire damper comprising atubular insert having a grid of intumescent material formed across thecircumference of the pipe or duct. However, although such an arrangementenables very quick sealing to occur, it has the disadvantage that itslows down the passage of fluid along the pipe or duct. Such a slowdownis amplified by the number of concrete slabs which the pipe or ducttraverses to the extent that complete blockage of the fluid canultimately occur.

OBJECT OF THE INVENTION

It is therefore an object of the invention to provide a new form of firecollar/fire damper which obviates the aforementioned disadvantages or atleast provides the public with a useful alternative.

SUMMARY OF THE INVENTION

According to the present invention in its broadest form, there isprovided a housing for fitting into pipework or ducting at the locationthe pipework or ducting traverses a partition, which housingincorporates a damper arrangement and a heat detector, wherein thedamper arrangement is designed to normally enable unimpeded fluid flowthrough the pipework or ducting but to seal off the pipework or ductingwhen the heat detector reacts to a preset temperature value.

By “fluid” is intended to mean gases, such as air-conditioning air,waste gases, and liquids such as liquid wastes and water.

DETAILED DESCRIPTION OF THE INVENTION

Preferably, the damper arrangement incorporates a cylinder or ball valvehaving an internal passageway which is of the same or similar diameterto that of the pipework or ducting in which it is fitted. The cylinderor ball valve is arranged so as to be rotatable about an axis so that itcan rotate between a normal open position where passage of fluid throughthe pipework or ducting is unimpeded to a position, generally at rightangles to the open position, where passage of fluid to prevented.

Rotation of the cylinder or ball valve can be achieved by mechanicaland/or electrical means. Mechanical rotation can be, for instance, bythe use of a spiral spring retained in a recess formed in an exteriorwall of the housing, having its outer end held by the housing and itsinner end held by the cylinder or ball valve. In its normalconfiguration, the spring is under tension but it cannot rotate the ballor cylinder to a closed position until the heat detector reacts to apreset temperature value. The closed position can be established by apin located in the housing wall which meets a stop when rotation through90° has been made.

In one form of the invention, the heat detector can be formed from amaterial which has the dual properties of, firstly, being capable ofbonding or interlocking with an element of the damper arrangement andthe housing and, secondly, being able to yield its bond or lock when itis heated to a predetermined temperature value. These properties enablethe heat detector to be designed and located in such a manner that itwill normally ensure that the damper arrangement is held open but when apredetermined, ie. preset, temperature is reached, it will yieldenabling the damper arrangement to close.

Suitable heat detector materials are lead and its alloys, plasticsmaterials and various composites. Typically, the temperature at whichsuch materials yield will be in the range of 60°-120° C., depending uponthe particular application, so as to meet governmental or local councilrequirements.

The heat detector material can be located, for instance, in the interiorperimeter of the housing where an element of the damper arrangement hasan adjacency when in an open configuration. Thus, in the case of a ballvalve, a circular seal of heat detector material, such as a ring of leadcan be located between the housing and the ball valve at both the inletand outlet sides.

In another form, the heat detector material can comprise an alloy padformed on the end of a bearing shaft which extends through the wall ofthe housing to a location within the damper arrangement, preferably at alocation which does not impede the flow of fluid through the housing. Aspiral spring retained in a recess on the outer side of the housingconnects the shaft to the housing. The spring is normally held undercompression and is only released from compression when the alloy padyields upon being heated to the preset temperature, thereby enabling theshaft and damper to rotate to a closed position.

In yet another form of the invention, the heat detector can be athermocouple. The thermocouple can be connected by way of appropriatecircuitry to a solenoid which can retract a pin extending between thehousing and the damper arrangement, to permit the damper arrangement toclose when the thermocouple detects a predetermined temperature value.Such a situation also permits the damper to be reset to an openconfiguration as well as the simultaneous operation of other firecollars within the partition.

In order to test the integrity of the fire collar/damper arrangement,testing means can be provided which enable the damper to be movedbetween its open and closed configurations. Such testing means can beautomatic or manual. An automatic testing means can comprise a motorwhich drives, for instance, the aforementioned bearing shaft so as torotate the attached damper. A manual testing means can consist of asimple lever fitted to the bearing shaft.

The fire collar according to the invention is ideally fabricated fromceramic materials but other materials such as fibre-reinforced concrete,metal and the like can also be used depending upon the specific usage.Preferably, the damper arrangement incorporates a cylinder or ball madefrom plastics material having an intumescent material embedded betweeninner and outer layers of the plastics material. The intumescentmaterial expands when the cylinder or ball has rotated to its closedposition, thereby providing an additional fire-stop feature.

Usage of the fire collar/fire damper can range across a large number offields from plumbing to ventilation and air-conditioning installations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a fire collar according to the invention showinga closed damper arrangement;

FIG. 2 is a top view of the fire collar shown in FIG. 1 with the damperarrangement open;

FIG. 3 is an end view of the fire collar shown in FIG. 1;

FIG. 4 is a side view of the fire collar shown in FIG. 1;

FIG. 5 is a side view of a fire collar according to another aspect ofthe present invention;

FIG. 6 is a side view of a fire collar according to yet another aspectof the present invention;

FIG. 7 is an end view of a fire damper assembly accordingly to still yetanother aspect of the present invention; and

FIG. 8 is a side view of the fire damper assembly of FIG. 7.

DESCRIPTION OF PREFERRED EMBODIMENTS

Preferred embodiments of the invention will now be described withreference to the drawings, in each of which like reference numeralsrefer to like parts.

Referring firstly to FIGS. 1-4, the fire collar comprises a ceramichousing 10 having a partially spherical ceramic ball valve 11, that is,the ball valve has two opposing sectors removed as can be seen in FIG.3, centrically located therein. The ceramic housing may be formed byheat welding two hemispheres together after the ball valve 11 has beenlocated therein.

The spherical ball valve 11 has a passageway 12 extending from one sideto the other with a diameter which corresponds to the diameter of thehousing inlet 13 and outlet 14. The housing inlet 13 and outlet 14, inturn, have diameters which do not impede the flow of fluid there throughfrom attached pipework or ducting. There is thus unimpeded fluid flowthrough the fire collar.

A recess 24 is formed in the outer wall of the housing and a stainlesssteel spiral spring 15 is located therein. The spiral spring has one end16 bent so as to be retained within a hub of the housing and the otherend 17 cranked for retention by the ball valve 11.

Two rings 18, 19 or lead alloy are bonded between the housing and theball valve, and additionally seal the end of the small gap, 20 betweenthe ball valve and its seat. The gap 20 can be maintained by smallridges formed on the surface of the ball valve. Such a gap is useful forpreventing binding between the ball valve and its seat such as couldpotentially occur over time.

Elastomeric seals 21, 22 enable quick secure fractional attachment to aplastics material ventilation pipe extending from a toilet or similarodour producing facility.

The fire collar depicted in FIGS. 1-4 is designed to be located within aconcrete slab of a high rise building. In use, the fire collar willmaintain the open configuration shown, for instance, in FIG. 2 untilsuch time as a fire occurs on either side of the concrete slab. When thefire reaches the ventilation-hydraulic pipe at the point of attachmentto the fire collar, and the temperature climbs to the pre-set value, thelead alloy ring seals 18, 19 melt and the ball valve is then free torotate under the tension of the spiral spring 15. Rotation continuesuntil the passageway 12 in the ball valve is in alignment with the inlet13 and outlet 14 at which point a stop pin 23 in the ball valve quadrantprevents further rotation.

Referring to FIG. 5, the fire collar comprises a two-part plasticsmaterial housing 50, 51 whose components press-fit together so as toenclose a partially spherical hollow plastics material ball 52 havingopposed openings so as to provide a through passageway for fluid when inan open configuration. The ball 52 includes an intumescent materialwhich is encased within the walls of the ball.

The ball 52 is rotatable between ah open and a closed position uponintegrally formed pivots 53, 54 which are housed in recesses formed inthe wall of the housing. Under normal, in use, conditions, the ball isretained in an open position by two rings of lead 55, 56 contained inannular recesses in the housing at the entry and at sides of the ball.

The ball 53 is held under tension in its open position by virtue of aflat coil spring 57. The spring is tensioned to rotate the ball throughninety degrees when the lead rings 55, 56 yield at a preset temperature.Continued rotation of the ball 53 is prevented by a stop 58 formed by awall of the housing.

The fire collar can be readily connected to the pipework by means ofcylindrical connecting elements 59 d, 59 b.

FIG. 6 is a modified version of the fire collar shown in FIG. 5. Thisversion enables the fire collar to be tested at desired intervals toensure that the ball can be rotated and has not become jammed orotherwise inoperable. The main difference from the FIG. 5 version isthat the heat detector component comprises an alloy pad 60 formed on theend of a square drive shaft 61. A secondary internal drive shaft 62 alsojoins with this alloy pad and connects to a pulley 63, which isrotatable by means of an actuating cable 64 connected to a motor 65.

In general use, the motor is actuated to rotate the fireball 66 betweenan open and closed position and back again, to test the integrity of thesystem at desired time intervals.

During a fire, the alloy pad 60 yields and the fireball 66 rotates underthe action of a coil spring 67, as the mechanical connection between thesquare drive shaft 61 and the internal drive shaft 62 is disengaged.

FIGS. 7 and 8 show a general damper arrangement which is based upon thesame principal of operation as the FIG. 6 embodiment.

The damper arrangement comprises a rotating damper 70 in which a heatdetecting metal alloy pad 71 is located with the same type of coilspring 72 and testing 73 set-up as described with FIG. 6.

The damper is connected to ducting at 74, 75 and is pivotal at 76.Intumescent material is located at 77, 78 and intumescent lip seals arepositioned at 79, 80.

The function of this damper is similar to that of the previousembodiment.

1-10. (canceled)
 11. A fire damper including: a housing having an inlet adapted to connect to an inlet conduit and an outlet adapted to connect to an outlet conduit; a damping member in said housing adapted to move from an open position in which the damping member allows fluid to flow from said inlet to said outlet to a closed position in which said damping member inhibits flow from said inlet to said outlet, said damping member having a passage therethrough with a passage inlet and a passage outlet, said passage inlet and said passage outlet being adapted to align with the inlet and outlet of said housing respectively when said damping member is in the open position and said damping member including an intumescent material.
 12. A fire damper according to claim 11, wherein said damping member is mounted for rotation about an axis extending across said housing.
 13. A fire damper according to claim 12 including biasing means for biasing said damping member to the closed position.
 14. A fire damper, according to claim 13, wherein said biasing means includes a spiral spring wound about said axis.
 15. A fire damper according to claim 14, wherein said damping member is mounted on a shaft which is supported for rotation in said housing about said axis.
 16. A fire damper according to claim 14, wherein said spiral spring is mounted between said damping member and said housing.
 17. A fire damper according to claim 13 including retaining means for retaining said damping member in the open position against the bias of said biasing means, said retaining means being adapted to release said damping member in response to heat whereby said biasing means can force said damping member to the closed position.
 18. A fire damper according to claim 17, wherein at least a portion of said retaining means is located in said housing and said portion is adapted to yield in response to said housing or fluid in said housing reaching a predetermined temperature.
 19. A fire damper according to claim 11, wherein at least a portion of said retaining means is located in said housing and said at least a portion is adapted to yield in response to said housing or fluid in said housing reaching a predetermined temperature.
 20. A fire damper according to claim 19, wherein said at least a portion of said retaining means is located adjacent said passage inlet.
 21. A fire damper according to claim 20, wherein said at least a portion of said retaining means is a ring which engages with said housing and said damping member so as to retain said damping member in the open position.
 22. A fire damper according to claim 21, wherein said retaining means is adapted to yield within a temperature range of 60 degrees Celsius and 120 degrees Celsius.
 23. A fire damper according to claim 22, wherein said retaining means is formed substantially of lead or a lead alloy or composite.
 24. A fire damper according to claim 17, wherein said retaining means releasably secures said damping member to said housing and is adapted to release said damping member in response to the ambient air reaching a predetermined temperature.
 25. A fire damper according to claim 24 including heat detection means adapted to detect temperature and actuate said retaining means.
 26. A fire damper according to claim 25, wherein said damping member is mounted on a shaft which is supported for rotation in said housing about said axis.
 27. A fire damper according to claim 26, wherein said shaft is a first shaft and said retaining means drivingly connects said first shaft to a second shaft.
 28. A fire damper according to claim 27, wherein said second shaft is drivingly connected to a drive motor.
 29. A fire damper according to claim 11, wherein said damping member is a cylinder valve or a ball valve.
 30. A fire damper according to claim 29, wherein said intumescent material of said damping member is encased by a plastics material.
 31. A fire damper according to claim 30, wherein said plastics material is molded about said intumescent material.
 32. A fire damper including: a housing having an inlet adapted to connect to an inlet conduit and an outlet adapted to connect to an outlet conduit; a damping member in said housing adapted to move from an open position in which the damping member allows fluid to flow from said inlet to said outlet to a closed position in which said damping member inhibits flow from said inlet to said outlet; biasing means for biasing said damping member towards the closed position; retaining means for retaining said damping member in the open position, and at least a portion of said retaining means being located in said housing and being adapted to yield upon fluid in said housing reaching a predetermined temperature so as to release said damping member.
 33. A fire damper according to claim 32, wherein said damping member has a passage therethrough with a passage inlet and a passage outlet, said passage inlet and said passage outlet being adapted to align with the inlet and outlet of said housing respectively when said damping member is in the open position.
 34. A fire damper according to claim 33, wherein said damping member is mounted for rotation about an axis extending across said housing.
 35. A fire damper according to claim 34, wherein said biasing means includes a spiral spring wound about said axis.
 36. A fire damper according to claim 35, wherein said spiral spring is mounted between said damping member and said housing.
 37. A fire damper according to claim 34, wherein said damping member is mounted on a shaft which is supported for rotation in said housing about said axis.
 38. A fire damper according to claim 33, wherein said at least a portion of said retaining means is located adjacent said passage inlet.
 39. A fire damper according to claim 38, wherein said at least a portion of said retaining means is a ring which engages with said housing and said damping member so as to retain said damping member in the open position.
 40. A fire damper according to any one of claims 32, wherein said retaining means is adapted to yield within a temperature range of 60 degrees Celsius and 120 degrees Celsius.
 41. A fire damper according to claim 40, wherein said retaining means is formed substantially of lead or a lead alloy or composite.
 42. A fire damper according to claim 32, wherein said retaining means releasably secures said damping member to said housing.
 43. A fire damper according to claim 42 including heat detection means adapted to detect temperature and actuate said retaining means.
 44. A fire damper according to claim 37, wherein said shaft is a first shaft and said retaining means drivingly connects said first shaft to a second shaft.
 45. A fire damper according to claim 44, wherein said second shaft is drivingly connected to a drive motor.
 46. A fire damper according to claim 32, wherein said damping member is a cylinder valve or a ball valve.
 47. A fire damper including: a housing having an inlet adapted to connect to an inlet conduit and an outlet adapted to connect to an outlet conduit; a damping member having a flow passage therethrough defined at least in part by first and second spaced apart opposed wall portions, said damping member being mounted in said housing for at least partial rotation from an open position in which said flow passage aligns with said inlet and said outlet to a closed position in which said first wall portion closes said inlet and said second wall portion closes said outlet; biasing means operatively connected to said housing for biasing said damping member towards the closed position; retaining means for retaining said damping member in the open position, said retaining means being adapted to release said damping member in response to heat; and a quantity of intumescent material in said housing and adapted to form a seal between said damping member and said housing upon expansion when said damping member is in the closed position.
 48. A fire damper according to claim 47, wherein said biasing means includes a spiral spring.
 49. A fire damper according to claim 48, wherein said spiral spring is mounted between said damping member and said housing.
 50. A fire damper according to claim 47, wherein at least a portion of said retaining means is located in said housing.
 51. A fire damper according to claim 50, wherein said at least a portion of said retaining means is a ring which engages with said housing and said damping member so as to retain said damping member in the open position.
 52. A fire damper according to claim 47, wherein said retaining means is adapted to yield within a temperature range of 60 degrees Celsius and 120 degrees Celsius.
 53. A fire damper according to claim 52, wherein said retaining means is formed substantially of lead or a lead alloy or composite.
 54. A fire damper according to claim 47, wherein said retaining means includes a pin which releasably secures said damping member to said housing and is adapted to release said damping member in response to the ambient air reaching a predetermined temperature.
 55. A fire damper according to claim 54 including heat detection means adapted to detect temperature and actuate said pin.
 56. A fire damper according to claim 47, wherein said damping member is mounted on a first shaft and said retaining means drivingly connects said first shaft to a second shaft which is drivingly connected to a drive motor. 